Machines for casting stereotype plates



March 27, 1962 A. v. B'UGLER 3,026,583

MACHINES FOR CASTING STEREOTYPE PLATES Filed Sept. 29, 1959 F/G.4 a

7r INVENTOR BY 3 Wu, 4M 1 a I ATTORNEYS nited States This invention relates to machines for casting curved stereotype plates used in printing.

It is concerned with that type of machine in which the plate is cast trom a matrix in a mould having a curved core and an arched back. Both the core and the back are jacketted for the flow therethrough of: cooling water.

The object of the invention is to provide in such a machine improved means for cooling the core so as to reduce the time for cooling the casting and thereby improve the production rate of the machine.

In the machine according to the present invention the core jacket houses means for spraying water to cool the core.

Preferably the arrangement is such that water sprays are directed against or at least towards the curved part of the core wall that forms part of the casting chamber. The spraying means may consist of water tubes which atent extend through the core chamber and jet the cooling water against the wall of the core. Thus a series of straight tubes are arranged concentrically within the core jacket and are supplied with cooling water under pressure from a manifold at one end of the core. The other end of the core has a water outlet.

It is preferred to jet the water sprays obliquely forward, at an angle of say 30, relatively to the direction of water flow through the tubes, and to arrange the jets to afford laterally flared sprays. The jets may be produced by transverse saw cuts extending through the walls of the tubes. In a modification the jets consist of holes.

It has been found that the high local velocity of water on the cooling surface has a marked effect in reducing the time for cooling a plate compared with the time entailed with the normal method oi bulk water flow through the core.

One form of the invention will now be described by way of example with reference to the accompanying drawings showing an arrangement in which the mould is arranged vertically.

FIG. 1 is a vertical section through the mould core, shown in a casting position;

FIG. 2 is a cross-section on the line II-II of FIG. 1;

FIG. 3 is a longitudinal section on a larger scale through one of the water tubes;

FIG. 4 is an elevation of a portion of a slotted water tube, also on a larger scale; and

FIG. 5 is an elevation of a portion of another form of water tube With holes instead of slots.

Although not essential to the invention, the mould back is fixed in a vertical position, and the mould core 11 is fitted to a hinge 12 at its lower end, so that it can be swung from the vertical operative position shown, in which the mould is shut for casting, to a horizontal position for opening the mould, from which position the cast plate is removed for any subsequent finishing operation.

The core 11 is of arched form and has a jacket 13 affording an ercnate water cooling chamber. The bottom of the jacket is drilled and tapped to receive five (or other suitable number of) screwed ferrules 14 with hexagon heads 15 fitted with tubes 16 welded at 19 which extend upwardly into the core water chamber to near its top. The set of tubes 16 is arranged close to and concentrically with the curved outer wall 17 of the jacket, which forms part of the plate casting chamber 18 in the mould. The upper end of each tube is closed at 19.

Water to the tubes 16 is supplied through an inlet port 20 in a manifold 21 bolted to the bottom of the core. Along each tube is made a series of saw cuts 27 extending transversely through the wall of the tube at an angle of about 30 to the axis of the tube in upward direction, i.e. in the direction of the water tube. The slots serve as jet orifices for throwing sprays of cooling Water under pressure against the outer wall 17 of the core. As each slot extends circumferentially round the tube, a flared jet is produced, which spreads laterally over the wall.

In the modification shown in FIG. 5 pairs of jet holes 22 are arranged to spray'water obliquely against the core wall 17 in radial directions to both sides of each tube. A third radial jet hole 23 is provided between each such pair of jet holes 22 for jetting cooling water in a direction normal to the wall.

To provide even cooling, the arrangement of tubes and slots or jet holes is such as to distribute cooling water as evenly as possible over the core Wall.

After traversing the core, the cooling water is discharged into the top manifold 24 of the core chamber through a short tube 25 and thence drained away through a flexible tube 26.

To increase the cooling rate, a pump may be utilized to augment the pressure of the mains supply so as to speed up the water flow and thereby the heat abstracted by the water.

What is claimed is:

l. A machine for casting curved stereotype printing plates comprising a core with upper and lower ends and having a cooling chamber, the outer wall of which is constituted by that part of the core defining the mold cavity and the inner Wall of which is constituted by a correspondingly curved plate substantially coextensive with said core part and arranged in close proximity thereto and which is provided with a fluid outlet at its upper end and is devoid of outlets except at its upper end, a plurality of spray tubes extending parallel to said outer wall Within said chamber, means to conduct a cooling fliud to the lower ends of said tubes, said spray tubes being formed to provide a multiplicity of jet orifice means having laterally obliquely directed portions and arranged to discharge laterally-flared sprays of cooling fluid into said chamber and against the inner face of said outer wall to fill the chamber and to impart a high local velocity to the cooling fluid in proximity to said outer Wall.

2. A machine according to claim 1, wherein the spraying tubes are arranged longitudinally of the cooling chamber and from one end to the other.

3. A machine according to claim 1, wherein the spraying tubes are straight and are arranged concentrically within the cooling chamber parallel to the core axis.

4. A machine according to claim 1, wherein the jets are arranged to spray the cooling fluid obliquely forward relatively to the direction of fluid flow through the cooling chamber.

5. A machine according to claim 1, wherein the jet orifice means of each tube are arranged to direct the sprays obliquely forward at an angle of about 30 to the longitudinal axis of the tube.

6. A machine according to claim 1, wherein the jet orifice means are afforded by saw cuts extending into the walls of the tubes.

7. A machine according to claim 1, wherein the jet orifice means are afforded by holes formed in the walls of the tubes.

8. A method of casting curved stereotype printing plates on the outer surface of a laterally-curved wall the inner surface of which forms the front wall of a laterallycurved cooling chamber having upper and lower ends, which comprises maintaining said chamber full of a cool- 3 4 ing liquid confined therein except at its upper end, and References Cited in the file of this patent imparting to the liquid in proximityto said inner surface UNITED STATES PATENTS a high local velocity by ejecting through the thus-confined cooling liquid and against said inner surface a multii phclty of upwardly-directed ets of cooling fluid at least 5 1:722:555 Bremner July 1929 portions of which are ejected toward and directed against said inner surface at angles which are oblique with re- REI N PATENTS spect to the lateral contour of said inner surface. 7,135 Great Britain 1908 

